Date of Graduation
Doctor of Philosophy in Space & Planetary Sciences (PhD)
Second Committee Member
Pure sciences; Applied sciences; Earth sciences; Dielectric constants; Planetary formation; Regolith; Shape formation; Subsurface structures
Subsurface planetary investigation techniques are of high interest and importance for the scientific community. Not only they can enhance our knowledge of the history of planetary formation but also can lead to information about its future. Whether the investigation is being conducted remotely using imagers, radars or physically using penetrometers or drills, a pre-existed knowledge of the mechanical and electrical properties of the subsurface regolith should be acquired for better data interpretation and analysis. Therefore, the main objective of this work is to investigate the mechanical and electrical properties of planetary analogs, understand their role for assessing the subsurface structure and identify their character for subsurface investigation techniques. Through-out this research, we investigated the mechanical and electrical properties of regolith analogs with emphasis on testing the feasibility of using penetrometer to explore the subsurface of planetary bodies and estimate their structure and layering. We found probe's diameter and regolith density are the most dominant factors which affect penetration forces. We correlated the mechanical and electrical properties of regolith analogs to geomorphological shape formation. An increase in gully total length corresponds to an increase in dielectric constant, friction angle and formation bulk density which will enhance previous, current and future modelling, interpretation and analysis of optical imagery and radar data. We performed dielectric permittivity and hardness measurements for volcanic rocks in order to provide a cross relation between the dielectric constant of the investigated material and its hardness property. A linear increase in dielectric constant observed along with an increase in rock hardness. This will enhance characterization of the shallow subsurface when investigated using radar and drill/penetrometer.
Elshafie, Ahmed, "Subsurface Planetary Investigation Techniques and Their Role for Assessing Subsurface Planetary Composition" (2012). Theses and Dissertations. 564.